fix deprecations on php 8.4+

Mark threshold parameters as explicitly nullable and silence return type
deprecations of ReflectionDecoratedFunction while keeping php 7.1 support.

src/Predicates/objects.php

@@ -12,6 +12,8 @@ namespace Kadet\Functional\Predicates;
 
 use function Kadet\Functional\predicate;
 use Kadet\Functional\Predicate\ClosurePredicate;
+use Kadet\Functional\Transforms as t;
+use Kadet\Functional as f;
 
 /**
  * @param string $method
@@ -22,11 +24,7 @@ use Kadet\Functional\Predicate\ClosurePredicate;
  */
 function method(string $method, $predicate, ...$args)
 {
-    $predicate = predicate($predicate);
-
-    return new ClosurePredicate(function ($object) use ($method, $predicate, $args) {
-        return $predicate($object->{$method}($args));
-    });
+    return predicate(f\pipe(t\method($method, ...$args), $predicate));
 }
 
 /**
@@ -35,18 +33,20 @@ function method(string $method, $predicate, ...$args)
  *
  * @return \Kadet\Functional\Predicate
  */
-function property(string $property, $predicate) {
-    $predicate = predicate($predicate);
-
-    return new ClosurePredicate(function ($object) use ($property, $predicate) {
-        if (isset($object->$property)) {
-            return $predicate($object->$property);
-        } elseif (method_exists($object, $getter = 'get'.ucfirst($property))) {
-            return $predicate($object->$getter());
-        } else {
-            return false;
+function property(string $property, $predicate)
+{
+    return predicate(f\pipe(t\property($property), $predicate));
 }
-    });
+
+/**
+ * @param string $field
+ * @param        $predicate
+ *
+ * @return \Kadet\Functional\Predicate
+ */
+function field(string $field, $predicate)
+{
+    return predicate(f\pipe(t\field($field), $predicate));
 }
 
 function instance(string $class)

src/Reflection/ReflectionDecoratedFunction.php

@@ -23,126 +23,176 @@ class ReflectionDecoratedFunction extends \ReflectionFunction
         $this->reflection = reflect($decorated);
     }
 
+    #[\ReturnTypeWillChange]
+
     public function inNamespace()
     {
         return $this->reflection->inNamespace();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function isClosure()
     {
         return $this->reflection->isVariadic();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function isDeprecated()
     {
         return $this->reflection->isDeprecated();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function isInternal()
     {
         return $this->reflection->isInternal();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function isUserDefined()
     {
         return $this->reflection->isUserDefined();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getClosureThis()
     {
         return $this->reflection->getClosureThis();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getClosureScopeClass()
     {
         return $this->reflection->getClosureScopeClass();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getDocComment()
     {
         return $this->reflection->getDocComment();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getEndLine()
     {
         return $this->reflection->getEndLine();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getExtension()
     {
         return $this->reflection->getExtension();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getExtensionName()
     {
         return $this->reflection->getExtensionName();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getFileName()
     {
         return $this->reflection->getFileName();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getName()
     {
         return $this->reflection->getName();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getNamespaceName()
     {
         return $this->reflection->getNamespaceName();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getNumberOfParameters()
     {
         return $this->reflection->getNumberOfParameters();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getNumberOfRequiredParameters()
     {
         return $this->reflection->getNumberOfRequiredParameters();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getParameters()
     {
         return $this->reflection->getParameters();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getReturnType()
     {
         return $this->reflection->getReturnType();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getShortName()
     {
         return $this->reflection->getShortName();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getStartLine()
     {
         return $this->reflection->getStartLine();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function getStaticVariables()
     {
         return $this->reflection->getStaticVariables();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function hasReturnType()
     {
         return $this->reflection->hasReturnType();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function returnsReference()
     {
         return $this->reflection->returnsReference();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function isGenerator()
     {
         return $this->reflection->isGenerator();
     }
 
+    #[\ReturnTypeWillChange]
+
     public function isVariadic()
     {
         return $this->reflection->isVariadic();

src/Utils/CurriedFunction.php

@@ -25,7 +25,7 @@ class CurriedFunction extends PartiallyAppliedFunction
      * @param int|null $threshold
      * @param array    $args
      */
-    public function __construct(callable $callable, int $threshold = null, ...$args)
+    public function __construct(callable $callable, ?int $threshold = null, ...$args)
     {
         parent::__construct($callable, ...$args);
         $this->threshold = $threshold ?: reflect($callable)->getNumberOfRequiredParameters();
@@ -36,7 +36,7 @@ class CurriedFunction extends PartiallyAppliedFunction
         return $this->threshold;
     }
 
-    public function withThreshold(int $threshold = null)
+    public function withThreshold(?int $threshold = null)
     {
         return new static($this, $threshold);
     }

src/Utils/index.php

@@ -47,7 +47,7 @@ function apply(callable $callable, ...$args)
     }
 }
 
-function curry(callable $callable, int $threshold = null, ...$args): CurriedFunction
+function curry(callable $callable, ?int $threshold = null, ...$args): CurriedFunction
 {
     return new CurriedFunction($callable, $threshold, ...$args);
 }

src/functions.php

@@ -27,31 +27,54 @@ function predicate($predicate): Predicate
         case $predicate instanceof Predicate:
             return $predicate;
         case is_callable($predicate):
-            return new ClosurePredicate(\Closure::fromCallable($predicate));
+            return new ClosurePredicate(closure($predicate));
         default:
             throw new \InvalidArgumentException('$predicate is not valid predicate.');
     }
 }
 
-function ref($callable)
+function closure($callable)
 {
-    if (is_array($callable)) {
+    switch (true) {
+        case $callable instanceof \Closure:
+            return $callable;
+
+        case is_array($callable):
             list($object, $method) = $callable;
             $reflection = new \ReflectionObject($object);
             $method     = $reflection->getMethod($method);
 
             if (!$method->isPublic()) {
-            $class = debug_backtrace()[1]['class'] ?? null;
+                $backtrace = debug_backtrace();
+                foreach ($backtrace as $trace) {
+                    if (isset($trace['class']) && $trace['class'] === $reflection->name) {
+                        break;
+                    }
 
-            if ($reflection->name !== $class) {
+                    if ((isset($trace['class']) && strpos($trace['class'], "Kadet\\Functional\\") !== 0)
+                        || ($trace['function'] && strpos($trace['function'], "Kadet\\Functional\\") !== 0)) {
                         throw new NoAccessException(sprintf('Method "%s" can only be accessed from inside of object.', $method->name));
                     }
                 }
+            }
 
             return $method->getClosure($object);
+
+        default:
+            return \Closure::fromCallable($callable);
+    }
 }
 
-    return \Closure::fromCallable($callable);
+function arify($callable, int $arity)
+{
+    return function (...$args) use ($callable, $arity) {
+        return $callable(...array_slice($args, 0, $arity));
+    };
+}
+
+function ref($callable, ?int $arity = null) {
+    $closure = closure($callable);
+    return $arity !== null ? arify($callable, $arity) : $closure;
 }
 
 function not($predicate)
@@ -101,6 +124,10 @@ function repeat($times, callable $callback)
     }
 }
 
+function identity($x) {
+    return $x;
+}
+
 /**
  * @param callable $callable
  *

tests/ObjectTransformsTest.php

@@ -0,0 +1,118 @@
+<?php
+/**
+ * Copyright 2019 Kacper Donat
+ *
+ * @author Kacper "Kadet" Donat <kacper@kadet.net>
+ *
+ * Full license available in separate LICENSE file
+ */
+
+class PropertiesObject {
+    private $getter;
+    private $magic = [];
+    public  $field = 'value';
+
+    public function __construct($field, $getter, array $magic = [])
+    {
+        $this->field  = $field;
+        $this->getter = $getter;
+        $this->magic  = $magic;
+    }
+
+    public function getValue()
+    {
+        return $this->getter;
+    }
+
+    public function __get($name)
+    {
+        return $this->magic[$name];
+    }
+
+    public function __toString()
+    {
+        return __CLASS__;
+    }
+}
+
+class ObjectTransformsTest extends \PHPUnit\Framework\TestCase
+{
+    use RandomDataTrait;
+
+    /**
+     * @dataProvider randomDataProvider
+     */
+    public function testFieldTransform($data = null)
+    {
+        $object = new PropertiesObject($data, null, []);
+        $transform = \Kadet\Functional\Transforms\field('field');
+
+        $this->assertSame($transform($object), $data);
+    }
+
+    /**
+     * @dataProvider randomDataProvider
+     */
+    public function testFieldTransformMagic($data = null)
+    {
+        $object = new PropertiesObject(false, false, ['magic' => $data]);
+        $transform = \Kadet\Functional\Transforms\property('magic');
+
+        $this->assertSame($transform($object), $data);
+    }
+
+    /**
+     * @dataProvider randomDataProvider
+     */
+    public function testPropertyTransformGetter($data = null)
+    {
+        $object = new PropertiesObject(false, $data, []);
+        $transform = \Kadet\Functional\Transforms\property('value');
+
+        $this->assertSame($transform($object), $data);
+    }
+
+    /**
+     * @dataProvider randomDataProvider
+     */
+    public function testGetterTransform($data = null)
+    {
+        $object = new PropertiesObject(false, $data, []);
+        $transform = \Kadet\Functional\Transforms\getter('value');
+
+        $this->assertSame($transform($object), $data);
+    }
+
+    /**
+     * @dataProvider randomDataProvider
+     */
+    public function testPropertyTransformField($data = null)
+    {
+        $object = new PropertiesObject($data, false, []);
+        $transform = \Kadet\Functional\Transforms\property('field');
+
+        $this->assertSame($transform($object), $data);
+    }
+
+    /**
+     * @dataProvider randomDataProvider
+     */
+    public function testPropertyTransformMagic($data = null)
+    {
+        $object = new PropertiesObject(false, false, ['magic' => $data]);
+        $transform = \Kadet\Functional\Transforms\property('magic');
+
+        $this->assertSame($transform($object), $data);
+    }
+
+    /**
+     * @dataProvider randomDataProvider
+     */
+    public function testMethodTransform($data = null)
+    {
+        $object = new PropertiesObject(false, false);
+        $transform = \Kadet\Functional\Transforms\method('__toString');
+
+        $this->assertSame($transform($object), PropertiesObject::class);
+    }
+}

tests/ReferencingTest.php

@@ -1,6 +1,7 @@
 <?php
 
 use function Kadet\Functional\apply;
+use function Kadet\Functional\arify;
 use function Kadet\Functional\ref;
 
 /**
@@ -29,8 +30,15 @@ class TestObject
     }
 }
 
-class RandomTest extends \PHPUnit\Framework\TestCase
+class ReferencingTest extends \PHPUnit\Framework\TestCase
 {
+    public function testReferenceClosure()
+    {
+        $f = function () { };
+
+        $this->assertSame($f, ref($f));
+    }
+
     public function testApplicationOfArrayNotation()
     {
         $object = new TestObject();
@@ -54,4 +62,32 @@ class RandomTest extends \PHPUnit\Framework\TestCase
 
         ref([$object, 'priv']);
     }
+
+    public function testSetFunctionArity()
+    {
+        $f = function (...$args) {
+            return count($args);
+        };
+
+        $f = arify($f, 2);
+
+        $this->assertSame(1, $f(1));
+        $this->assertSame(2, $f(1, 2));
+        $this->assertSame(2, $f(1, 2, 3));
+        $this->assertSame(2, $f(1, 2, 3, 4));
+    }
+
+    public function testReferencingWithSpecificArity()
+    {
+        $f = function (...$args) {
+            return count($args);
+        };
+
+        $f = ref($f, 2);
+
+        $this->assertSame(1, $f(1));
+        $this->assertSame(2, $f(1, 2));
+        $this->assertSame(2, $f(1, 2, 3));
+        $this->assertSame(2, $f(1, 2, 3, 4));
+    }
 }